Accelerating pump



Patented Mar. 28, 1950 PATENT OFFICE ACCELERATING PUMP I Bert Beard,Detroit, Mich., asslgnor to George M. Holley and Earl Holley ApplicationFebruary 27, 1947, Serial No. 731,216

1 Claim.

The object of this invention is to improve the acceleration generallyandspecifically the part throttle accelerationi or foif idle" operationof I an automotive carbureto at opening I 6. In addition pure air entersthe tube 20, flows through the passage 38 and discharges on the engineside of the throttle i2 through the restricted opening it. As a resultof this very little air is taken in around the-lip of the throttle it.

A lever ie is shown above the level of the sectional carburetor and isconnected to the throttle shaft 52. The lever it is connected throughthe link 54 with the S-shaped element 4 which is shown above the planeof the cross-section of the drawing. This element 44 is guided in thebody of the carburetor and is connected by a one-way connection to thepump rod 50. The rod 50 slides in a hole in the end of the element 44. Aspring 56 surrounds the rod 50 and engages with the piston 42 and withthe underside of the upper portion of the element 44. Piston 42reciprocates in cylinder 30.

A float chamber 24 is connected through the passage 25 past the checkvalve 28 so that when the piston is moved up into the position shownfuel flows from the float chamber 24 into the pump cylinder 30. Fuel isdischarged from the pump cylinder 30 past the check valve 32 into I thepassage 34. Passage 34 discharges through the opening 36 into the airpassage.

Operation opening 36 and is carried through the opening 40 into themixture outlet.

When part throttle accelerating occurs the throttle l2 first opens toplace the opening IS on the engine side of the throttle and thereafter 2only opens far enough to admit part of the air that the engine callsfor. A considerable suction exists at the orifice 40 even after thethrottle 12 has been opened a considerable number of 5 degrees and thefuel for acceleration is properly atomized by engine suction so that avery satisfactory acceleration results.

During normal idle running the air delivered through passages 2@-3d idis pure air, hence, less air is taken in past the lips of the throttleit. By reducing this air flow around the throttle if, as pointed out inmy Patent No. 2,263,027, less freezing results in icing weather(moderate temperatures and high humidity), especially when operating atnormal idle speed with throttle 52 almost closed. Less air down passageiii means a richer mixture discharges at orifices iii and it. Thisricher mixture is less liable to freeze than are the mixtures in generaluse today.

The smaller the opening movement of the throttle if the greater is theatomization of the acceleration fuel supplied by pumps i i-3@ l2.

ft is touch throttle acceleration conditions which have been mostdifficult to satisfy. The slightest touch of the throttle will lift thesmall ball check valve 32, which is unloaded and so raises the level inthe vertical well 34. This causes fuel to flow out of the opening 36,down passage 38 to the restricted outlet 4t.

What I claim is:

Fuel acceleration means for a downdraft carburetor having a constantlevel fuel supply chamber, a main fuel nozzle fed therefrom, a mixturechamber into which the nozzle dis- 35 charges, a mixture outlet andbutterfly throttle therein, a low speed fuel nozzle connected to themain fuel nozzle and discharging fuel and air into said mixture outletat a point adjacent to the upstream lip of said throttle when saidthrot- 0 tle is in its idling position and in its initial runningposition comprising, a descending air passage of relatively large sizein free communication with the atmosphere at its upper end and arestricted lower outlet therefrom discharging a portion of the airrequired for low speed running into the mixture outlet on the engineside of and remote from said throttle, an accelerating pump operated bysaid throttle, a cylinder therefor, an inlet to said cylinder from saidconstant level 50 fuel supply chamber, an outlet passage from saidcylinder, an unloaded non-return valve therein. said passage discharginginto the unrestricted iii portion'ot said air passage so that fuel isdischarged by said pump uninfluenced by engine 'suction as the throttleis opened from its engine .idling position into its running position.

BERT BEARD.

REFERENCES CITED The following references are of record in the tile ofthis patent:

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